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<head>
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    <title>Document</title>
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<body>
    <script>
        var nam1 = parseInt(prompt('请输入'))
        var nam2 = parseInt(prompt('请输入'))
        var new2 = alert('结果是:' + (nam1 + nam2))
        var new3 = alert(0.1 + 0.3)
    </script>
</body>

</html>